The Thanksgiving matchup between the Dallas Cowboys and the Philadelphia Eagles was a crucial game for both teams. They went into the game with identical 8-4 record with the NFC East crown hanging in the balance.

The Eagles came away with the crucial win in a dominating 33-10 win over their division rival. Many may point to the way the offense effortlessly executed their game plan on their way to 33 points as the biggest reason the Eagles came away from AT&T Stadium with a victory.

Nevertheless, the most impressive aspect of the Eagles performance was how well their defense limited and downright dominated the vaunted Cowboys offense.

After their near flawless performance, Eagles’ head coach Chip Kelly had this to say about his defense’s execution, “They’ve got weapons like Witten and Dez Bryant, obviously, and Tony.  They’re playing really, really well on the offensive side of the ball so I thought our defense overall did a really nice job.”

“A really nice job” is putting it lightly.

The Cowboys have one of the most efficient offenses in the NFL; they have one of the best rushing attacks and an extremely potent passing attack led by Tony Romo. Dallas averages 231.9 passing yards and 145.3 rushing yards per game. Against the Eagles, they only managed 199 passing yards and 93 yards rushing.

How did an Eagles team that allows 366.3 yards per game hold the Cowboys to under 300 yards?

Some have pointed to the Cowboys predictability on offense as a reason why the Eagles were able to do such a good job.

While the Cowboys do need to be less predictable on offense, the real reason the Eagles were able to limit Dallas’ offense was because they were able to win the individual matchups throughout the game.

Fletcher Cox had his way with Ronald Leary throughout the game. Brandon Graham was able to be the spark plug for the Eagles pass-rush as he had four total pressures (one sack) in 12 pass rushing snaps per Pro Football Focus. Philadelphia’s defensive line was able to control the line of scrimmage and limit DeMarco Murray’s ability to get to the second level of the defense.

While those were all extremely important battles that the Eagles were able to control, the most impressive one may have been the way Philadelphia took Dez Bryant out of the game.

Dez is one of the most prolific wide receivers in the NFL. Going into the Thanksgiving Day matchup, Bryant was tied for the lead in touchdowns and ninth in receptions and receiving yards per PFF. Nonetheless, against the Eagles, Bryant was limited to four catches for 73 yards as he didn’t make a discernible impact on the game at all.

The Eagles put a great deal of trust in their cornerbacks as they played a large quantity of single-high safety with man coverage underneath. This puts a great deal of pressure on the cornerbacks as they only have help in the deep middle. This allowed the Eagles to put more players in the box to deal with Dallas’ dominant running game.

This would have been all for not, if the Eagles secondary didn’t do their job. As evidenced in the Eagles game against the Green Bay Packers, when their cornerbacks don’t do their job it severely limits how effective their defense can be. If the Cowboys were able to get their passing game going, the Eagles would have had to put a player out of the box, which would have given the Cowboys favorable running situation and led to a much more effective ground game.

Having said that, the Eagles secondary did their jobs and in doing so, they stopped one of the scariest wide receivers in the game.

The Eagles cornerbacks were able to curb Bryant’s productiveness was with their physicality.

The best way to take a receiver out of the game is by getting physical with him early in his route as to disrupt his timing with the quarterback. If a cornerback is able to get their hands on a receiver and redirect his route, they win.

The Eagles were able to do this early and often to Bryant, here is a great example:

Dez is lined up with a “numbers” split on the left side of the offense with Cary Williams opposite him in man coverage. After the snap, Bryant fires off the ball as Williams goes into a short and choppy back pedal. Once Bryant gets into striking distance, Williams gets his hands into Bryant and redirects the stem of his route to the outside.

This puts Williams in a great position because there are only a certain number of routes that Bryant can effectively run with an outside release. Therefore, Williams can use the sideline as his extra defender and limit the amount of space Bryant has to work with. This allows Williams to stay tight to Bryant’s inside hip and drive hard on the ball as Dez runs his comeback route, which results in a pass break up for Williams.

This physicality really got into Bryant’s head as the game went along.

Take a look at this play in the fourth quarter:

Bryant is lined up at a “plus” split with Bradley Fletcher opposite him in man coverage. You can see that the score, Eagles defense or a combination of the two, got into Bryant’s head as he runs an extremely sloppy and lazy route. He comes off with an outside release with no drive and doesn’t even attempt to run a real route.

This is not what you want to see from a star receiver or one of the leaders of your team. Notice how every other receiver at least makes an attempt to run a route. Even if he knew the ball wasn’t coming to him, Bryant has to at least put some effort into the play.

Now, the Eagles did employ some other coverages as well. On occasion, the Eagles would use a linebacker or safety to “buzz” underneath Bryant to help take away throwing lanes on any slants or crossing routes.

Still, the large majority of snaps had Bryant in one-on-one coverage with an Eagles cornerback. Some of Bryant’s ineffectiveness is due to Tony Romo and his inability to throw accurate passes throughout the game. However, it was mostly due to the fact that Dez failed to get open against single coverage for a majority of the game.

From a Cowboys perspective, Bryant has to be better. Your star receiver needs to be single coverage on a regular basis, especially because the Cowboys don’t have many players who can beat single coverage on a regular basis. Bryant is the backbone of the Cowboys passing game and he must put forth a better effort going forward.

From an Eagles point of view, they just executed their defensive game plan to a tee. Their ability to play man coverage outside allowed them to stop the run and put pressure on Romo throughout the game.

In their most important game of the season, the Eagles put together their best performance of the season.